1. Field of the Invention
The present invention relates to a method for dehydrating a water-containing substance using a liquefied matter, and, more particularly to a dehydration method and a dehydration system in which contained water can be efficiently eliminated at operation temperature close to outdoor air temperature with small required power and which are applicable to water-containing substances in wide fields regardless of a contained water content and a type thereof.
2. Description of the Related Art
Water-containing substances exert inherent advantages that they does not tend to spontaneously combust owing to contained water. However, they have problems in terms of bulky weights and hygiene. Upon treating the water-containing substance as a raw material or a starting material, the contained water can become an obstacle.
As dehydration methods for the purpose of eliminating the contained water from the water-containing substance utilized in such a case, a variety of methods have been developed and utilized depending on types of the water-containing substances.
In paper diapers and sanitary products, high performance absorbers which have a water absorbable capacity several hundred times higher than their own weights and keep a water retention capacity even when pressure is applied are used as major materials. Thus, they have an excellent property in retaining a large amount of water, whereas the increased weight after its use results in difficulty in transportation upon disposal. If the contained water can be separated, then the materials of the paper diapers may be reused, and it is anticipated that total waste amount can be reduced, which is preferable in terms of resource conservation.
Consequently, the techniques for removing urine and blood from the used paper diapers and sanitary products are being developed for proposal. For example, there has been reported a technique in which the used paper diaper which contains water such as that of urine is immersed in an aqueous solution of a detergent and calcium chloride to expel the contained water from the paper diaper, simultaneously the diaper is pulverized to fractionate into plastic, absorbable polymer and pulp by a wet gravity separation method, and the pulp among them is collected to reuse as a raw material of the paper diaper (Patent document 1).
In organisms such as animals, plants and microorganisms, the contained water occupies a majority of components thereof. Upon disposal, handling or preservation of such an organism, removal of water may trim weights and make treatments easy. For example, there is a necessity to eliminate jelly fish because it prevents hydroelectric power generation. The majority of the content of jelly fish is water. Thus, it is anticipated that if the contained water is eliminated, handling such as disposal becomes easy, and various dehydration techniques have been developed.
One example of the dehydration technique for the jelly fish is as follows: landed floating organisms (nektons) whose major content is the jelly fish are pulverized. Alum and an antioxidant is then infused for stabilizing and deodorizing the jelly fish-mashed water while solid contents and the contained water (treated water) are separated using a coagulant in a pressure flotation separation equipment. Subsequently, the solid contents are treated using a dehydrator and the contained water is treated using a wastewater treatment equipment (e.g., see Patent document 1).
Another method proposed is as follows: the landed floating organisms (nektons) whose major content is the jelly fish are pulverized, and the solid contents of the jelly fish are degraded with an enzyme, which are then treated using the wastewater treatment equipment (e.g., see Patent document 2).
Non-patent document 1: Care Root Service K.K., Caring and Welfare News,    http://www.careroot.co.jp/info_copy11.html    Patent document 1: JP 2001-187379 A Publication    Patent document 2: JP 2003-53303 A Publication